mjr wrote: ↑2 Aug 2021, 7:23pm
They are essential as part of the counterbalance of the rim strengthener in the join opposite the valve. Without it, the valve alone weighs less than the opposite side and your wheel will be unbalanced and inefficient, with energy wasted making its centre of mass orbit the hub.
Not all rims are joined with a tenon opposite. Some are welded and filed. These are those without a hollow section. I am not sure whether any are still produced in this way.
I annot remember any detectable problems with such wheels.
It's the same the whole world over
It's the poor what gets the blame
It's the rich what gets the pleasure
Isn't it a blooming shame?
My tube valves aren't threaded so don't have the retaining collar.
I have seen threadless valves with a little rubber o-ring.Not sure if this does anything but eliminate rattle on the extended valves?
thirdcrank wrote: ↑2 Aug 2021, 8:00pm
I've used Michelin valves which weren't threaded to take a locknut. I found it wasn't easy to get started with a push on pump. On valves with the locknut, I got into the habit long ago of slackening them off a bit once the tyre was pumped up. I once had a puncture which deflated the tyre very quickly and the valve was ripped out of the tube by the locknut.
If your valve had not been restrained by the locknut, what would have happened, I wonder?
Would the valve have been pulled out of its hole in the rim and moved safely with the tube?
Perhaps, if you stopped quickly, or perhaps it would have stuck in the hole and rpped out anyway.
It's the same the whole world over
It's the poor what gets the blame
It's the rich what gets the pleasure
Isn't it a blooming shame?
Stevek76 wrote: ↑2 Aug 2021, 7:27pm
I find them useful for getting a pump on when theres no or very low pressure in the inner tube.
They're pretty much essential for that, I find, or at least highly desirable, if it's a press-on, not screw-on, pump.
Many presta valves have no lock nut, so not essential. It may be a little more fiddle, but I manage by pushing the valve from the inside, i.e. tyre side.
It's the same the whole world over
It's the poor what gets the blame
It's the rich what gets the pleasure
Isn't it a blooming shame?
Stevek76 wrote: ↑2 Aug 2021, 7:27pm
I find them useful for getting a pump on when theres no or very low pressure in the inner tube.
They're pretty much essential for that, I find, or at least highly desirable, if it's a press-on, not screw-on, pump.
Many presta valves have no lock nut, so not essential. It may be a little more fiddle, but I manage by pushing the valve from the inside, i.e. tyre side.
I was thinking of Schraeder valves - I've only got one bike with Prestas, and right enough, the valve is so long and the tyres so narrow (25mm compared with 50mm on my Schraeder valve tyres) that now that I think about it I wouldn't really need the nut. So I suppose it's also to do with the length of the valve - I've got inner tubes where the valve is a bit too short and it sinks too far into the tyre when I try to get a push-on pump on to it unless it has a nut on it - and the width of the tyre - maybe even the rim section.
kylecycler wrote: ↑2 Aug 2021, 7:51pm
They're pretty much essential for that, I find, or at least highly desirable, if it's a press-on, not screw-on, pump.
Many presta valves have no lock nut, so not essential. It may be a little more fiddle, but I manage by pushing the valve from the inside, i.e. tyre side.
I was thinking of Schraeder valves - I've only got one bike with Prestas, and right enough, the valve is so long and the tyres so narrow (25mm compared with 50mm on my Schraeder valve tyres) that now that I think about it I wouldn't really need the nut. So I suppose it's also to do with the length of the valve - I've got inner tubes where the valve is a bit too short and it sinks too far into the tyre when I try to get a push-on pump on to it unless it has a nut on it - and the width of the tyre - maybe even the rim section.
I see.
I am trying to imagine how you fit the tube in the first place.
It's the same the whole world over
It's the poor what gets the blame
It's the rich what gets the pleasure
Isn't it a blooming shame?
Many presta valves have no lock nut, so not essential. It may be a little more fiddle, but I manage by pushing the valve from the inside, i.e. tyre side.
I was thinking of Schraeder valves - I've only got one bike with Prestas, and right enough, the valve is so long and the tyres so narrow (25mm compared with 50mm on my Schraeder valve tyres) that now that I think about it I wouldn't really need the nut. So I suppose it's also to do with the length of the valve - I've got inner tubes where the valve is a bit too short and it sinks too far into the tyre when I try to get a push-on pump on to it unless it has a nut on it - and the width of the tyre - maybe even the rim section.
I see.
I am trying to imagine how you fit the tube in the first place.
I was maybe exaggerating about how short the valve was - it sticks out far enough to fit the tube and screw a pump on to it to blow it up, it just tends to be awkward to fit a push-on pump on it (without a nut) when it's flat. Sometimes when I'm fitting a tube at home I start it off with a screw-on pump, then when it has enough pressure I'll switch to the push-on track pump. I've ditched these tubes anyway - I always try to make sure the valve is long enough for it not to be a problem but the nuts help.
kylecycler wrote: ↑3 Aug 2021, 11:54am
I was maybe exaggerating about how short the valve was - it sticks out far enough to fit the tube and screw a pump on to it to blow it up, it just tends to be awkward to fit a push-on pump on it (without a nut) when it's flat. Sometimes when I'm fitting a tube at home I start it off with a screw-on pump, then when it has enough pressure I'll switch to the push-on track pump. I've ditched these tubes anyway - I always try to make sure the valve is long enough for it not to be a problem but the nuts help.
My track pump and road pump both have lever-lock heads.
I dislike push ons because the washer tends to wear and its fit deteriorate.
It's the same the whole world over
It's the poor what gets the blame
It's the rich what gets the pleasure
Isn't it a blooming shame?
I make a point of buying only inner tubes with a smooth valve barrel, Michelin or some Decathlon, for example. Thumb pressure through the tyre is enough to enable pushing on a chuck and the smooth barrel doesn't wear the rubber washer in the chuck head. Make sure you buy tubes with the correct length valve for your rims. The 'dust caps' only serve to protect folded or rolled tubes, and can also be dispensed with in normal road conditions.
kylecycler wrote: ↑3 Aug 2021, 11:54am
I was maybe exaggerating about how short the valve was - it sticks out far enough to fit the tube and screw a pump on to it to blow it up, it just tends to be awkward to fit a push-on pump on it (without a nut) when it's flat. Sometimes when I'm fitting a tube at home I start it off with a screw-on pump, then when it has enough pressure I'll switch to the push-on track pump. I've ditched these tubes anyway - I always try to make sure the valve is long enough for it not to be a problem but the nuts help.
My track pump and road pump both have lever-lock heads.
I dislike push ons because the washer tends to wear and its fit deteriorate.
My track pump has a lever-lock head, sorry. I just meant you have to push it on to the valve first before you lock the lever!
The road pump I use for the road bike's 25mm tyres is the Lezyne one with a screw-on hose, but it has the pressure release valve that you press before you screw it back off, to prevent you unscrewing the valve. It seems to work ok.
I think they have 2 advantages, helping stop the valve fretting in the hole and making it easier to get a pump on a uninflated tube. The Schwalbe ones that correctly locate a presta vale in a Schrader hole are especially useful. I can see that you might have trouble getting one off if you've done it up too tight or if it's corroded. It's never happened to me though (yet) and in my experience what happens is they loosen themselves and rattle if left to their own devices.
All my pumps are lever lock and there's usually enough friction unlocked to still make it annoying, particularly if the valve is a bit short for the rim. Used schraders with nuts on my old mtb for the same reason.
The contents of this post, unless otherwise stated, are opinions of the author and may actually be complete codswallop
MartinC wrote: ↑3 Aug 2021, 1:16pm
I think they have 2 advantages, helping stop the valve fretting in the hole and making it easier to get a pump on a uninflated tube. The Schwalbe ones that correctly locate a presta vale in a Schrader hole are especially useful. I can see that you might have trouble getting one off if you've done it up too tight or if it's corroded. It's never happened to me though (yet) and in my experience what happens is they loosen themselves and rattle if left to their own devices.
It's not corrosion etc. It's temperature. If it ever happens to you you'll curse them! But I agree about advantages if you don't have a locking pump. It's a choice of enemies
